The invention relates to multiphase soaps in which the individual phases are highly visible when viewed from above and from the side, to their preparation and to their use for the application of different scent experiences during the washing operation.
DE-A 31 45 813 describes the preparation and use of picture and changing motif soaps. The preparation takes place by stamping various horizontal soap layers which have been prepared by means of an extruder. This process cannot be operated efficiently, meaning that use of these soaps is not possible in the mass consumer market. A particular disadvantage of this type of horizontally cut soap is the fact that the different horizontal soap layers cannot be distinguished or can be distinguished only with great difficulty by the consumer when viewed from a customary viewing angle of about 45xc2x0 and above. This effect intensifies with increasing use time since the two phases become thinner as a result of being washed off.
This disadvantage also applies to the diverse horizontally cut soaps described in EP-A 0 366 209 and U.S. Pat. No. 5,198,140. U.S. Pat. No. 5,198,140 describes the preparation of an interlocked soap having increased strength. EP-A 0 366 209 describes the preparation of horizontal multiphase soaps by a casting process. However, casting processes are only suitable for the preparation of small numbers of bars, but not for the production of soaps for the mass consumer market.
EP-A 0 594 077 describes the preparation of spiral-shaped multiphase soaps which are prepared using a special compression head following radial rotation of the soap strand. Particularly in cases where different soap bases are used, the stability of the type of soap is limited in its application by the many phase boundaries.
DE-A 1 924 980 describes a process for the preparation of a multiphase soap with one or more sheaths which surround a core. This type of soap cannot be differentiated visually by the consumer from a normal single-phase soap before use and also in between during use, as a result of which there is no applications-related advantage.
The same also applies to soaps prepared in accordance with JP-A 62/48799. Here, a multilayer round strand is produced.
Soaps are also known in which a vertical cut in the transverse or in the longitudinal direction of the soap separates the two soap phases (e.g., JP 1-247499). In this type of soap, both phases are visible at the same time. However, the vertical type of soap, during use by the consumer and during continuous storage, exhibits the decisive disadvantage of lower stability of the overall bar of soap. Because of the small and straight contact areas, a vertically cut soap may break even as a result of the soap simply falling to the ground. In particular, when different soap formulations are used for the individual parts of the soap, shrinkage and drying out can lead to breaking of the soap. Also, when different soap formulations are used, the strength of the diagonally cut soap, in contrast to vertically joined soap, is ensured during use by the consumer over the entire use period. As a result, it may, in the future, also be possible to combine less expensive soap formulations with more expensive soap formulations, or to combine different soap formulations, which are incompatible with one another because of shrinkage, for the preparation.
EP-A 0 545 716 describes the preparation of a multidimensionally curved two-phase soap. By using the casting process, a two-phase soap is produced, which is not suitable for the mass consumer market due to the costly preparation. Since the soap here is a cast soap in which no pressure is subsequently exerted in the form of stamping, the durability of this type of soap is limited during daily use.
Marbled soaps are also known (DE-A 2 455 982, DE 2 431 048, U.S. Pat. No. 1,587,430 and DT 1 953 916). Here, differently colored soap phases are mixed intensively with one another using special pressing cylinders or screw presses, such that a marbled effect arises. Furthermore, the color can also be injected into the soap stream during the preparation of the soap. The soaps here consist of one phase.
A further multicolored single-phase soap is described in U.S. Pat. No. 4,435,310. Here, by injecting color during the preparation of the soap strands and by manually turning the extruder head, a multicolored sinusoidal soap is obtained from one cake.
The objects of the present invention were multiphase soaps in which the different phases may have different ingredients which, during use, have a stability comparable with that of a single-phase soap. In particular, it is possible for the different phases to comprise different perfume oils so that, during use, different successive scent experiences are possible.
We have found multiphase soaps comprising two or more phases which are characterized in that the latter are highly visible when viewed from above and from the side.
The multiphase soaps according to the present invention exhibit superproportional strength, which virtually corresponds with the stability of a single-phase soap.